Tucked into the south-eastern quadrant of the fort's inner enclosure, excavators found not a habitation site in any quiet domestic sense, but what appears to have been a place of sustained industrial production, where metal was worked, cast, and smelted on a significant scale.

The evidence came to light during excavation carried out by the North Munster Project of the Discovery Programme in 1993. The debris recovered from the hill summit pointed to iron smelting, bronze smelting, and bronze casting all taking place in the same area, alongside the manufacture of querns, the rotary stone hand-mills used to grind grain. Radiocarbon dating placed the activity in the late Iron Age, returning a date of approximately 47 BC to 113 cal AD. That range puts it roughly in the period when Iron Age Ireland was producing elaborate metalwork of considerable sophistication, and the combination of iron and bronze working at a single enclosed hilltop site speaks to a community with both the raw materials and the specialist knowledge to exploit them. Mooghaun itself had already attracted attention long before this excavation: a remarkable Bronze Age gold hoard, one of the largest ever found in western Europe, was discovered near the fort in the nineteenth century, suggesting the area had drawn people with an interest in metal and its prestige for well over a millennium before the late Iron Age smiths set up their furnaces on the summit.